UPDATE 11.45AM: Rock falls and surface flooding on State Highway 1 around Kaikoura have forced the closure of the coastal road less than a month after it was re-opened.

It's only three weeks since the coastal highway, rebuilt after the Kaikoura earthquake, opened to holiday traffic.

The New Zealand Transport Agency says it's now closed between Mangamuanu and Clarence, north of Kaikoura, and Goose Bay to Peketa in the south.

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Motorists are being advised to take inland routes, including Lewis Pass.

"We have more certainty around this route in the current weather," NZTA journey manager Tresca Forrester said.

In the North Island, SH2 through the Waioeka Gorge, between the Bay of Plenty and Gisborne, is also closed, because of two large slips.

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Auckland's Northern Motorway has also been closed because of flooding.

Local detours are in place for southbound traffic on SH1 between the Northcote off-ramp and Onewa on-ramp.

Tamaki Drive in the eastern suburbs is also closed.

The Thames Coast Road (SH25) is among those also closed at present.